1. Technical Field
The present invention relates to warming applications. More specifically, the invention relates to methods, systems, and devices for warming fluid storage and dispensing systems and fluid stored therein or delivered therewith.
2. The Relevant Technology
In recent years, environmental concerns have been receiving significantly more attention, and various governmental agencies have responded by implementing stringent regulations to reduce or prevent pollution. Many of these regulations and concerns are directed towards vehicle emissions. For example, medium and heavy-duty trucks, especially diesel trucks, and large agricultural equipment, such as tractors, produce large amounts of pollutants that are believed to be harmful to the environment. Thus, some environmental regulations are requiring that such vehicles now be made to produce fewer harmful pollutants or, for existing vehicles, be retrofitted with systems that reduce the amount of pollutants released into the environment.
In order to comply with these environmental regulations, most diesel engine manufacturers are using Selective Catalytic Reduction (SCR) technology. The SCR system uses diesel exhaust fluid to convert nitrogen oxides (“NOx”) emissions into nitrogen and water vapor, which are two harmless and natural components. NOx are an exhaust element that contributes to acid rain, smog and greenhouse gas levels. This environmental pollutant is a byproduct of the high temperature diesel combustion process. The hotter the combustion temperature, the more NOx is created.
The Selective Catalytic Reduction system is an emissions-reduction technology using Diesel Exhaust Fluid (DEF) to deliver near-zero emissions of NOx. SCR reduces NOx emissions to extremely minute levels, while at the same time delivering improved fuel economy and reliability. SCR technology does not change the design or operation of the basic engine. Rather, SCR is a simple after treatment system that converts NOx in the exhaust stream into harmless gases. Modern diesels already use exhaust after treatment systems, called diesel particulate filters, to control emissions of other pollutants, such as soot (also known as particulate matter or PM). SCR works by injecting diesel exhaust fluid into the exhaust stream only as required. The diesel exhaust fluid works with the heat of the exhaust and a catalyst to convert NOx into nitrogen and water vapor.
Diesel exhaust fluid is one of the key elements of the Selective Catalytic Reduction process used by many vehicle engines to reduce the amount of harmful pollutants being introduced into the environment. Diesel exhaust fluid is a nontoxic solution of about 67.5% purified water and 32.5% ultra pure automotive grade urea. Diesel exhaust fluid is not a fuel or fuel additive. Instead, when injected into the exhaust stream and passed over a catalyst, Diesel exhaust fluid helps convert NOx into nitrogen gas and water vapor, which are harmless to the environment.
While SCR technology can be employed to help vehicles meet the increasingly more stringent environmental regulation, there are some challenges that are associated with this technology. Vehicles equipped with SCR systems have a tank for holding the diesel exhaust fluid used in the SCR system. For over the road vehicles, such as semi-trucks, these tanks can be filled at a filling station, such as a gas station, that provides diesel exhaust fluid. In other situations, such as agricultural settings, a diesel exhaust fluid supply may be located on a farm for refilling farm tractors, for example. In either case, the diesel exhaust fluid supply typically includes a fluid tank for storing the diesel exhaust fluid and a dispensing system for delivering the fluid from the storage tank to the vehicle. One challenge arises when temperatures drop. For instance, during cold winter months, temperatures may drop far enough that the diesel exhaust fluid freezes. In such a circumstance, the diesel exhaust fluid would not be able to be transferred from the storage tank to the vehicle tank. As a result, the vehicle may be operated without diesel exhaust fluid, which would lead to pollutants being introduced into the environment as well as decreased engine horsepower.
Thus, there is a need for systems, methods, and devices that can prevent the diesel exhaust fluid from becoming frozen, and thereby ensure that vehicles' SCR systems can be supplied with the necessary diesel exhaust fluid even in very low temperature situations.
The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced.